1. Field of Invention
This invention relates generally to flexible packages and more particularly to flexible packages including a fitment for dispensing a metered amount of liquid within the packages.
2. Description of Related Art
Numerous patents disclose flexible packing for holding liquids and for dispensing the liquid through a fitment outlet or tap forming a portion of the package. See for example, U.S. Pat. No. 4,429,810 (Hample et al.), U.S. Pat. No. 3,696,969 (De Van et al.), U.S. Pat. No. 4,314,654 (Gaubert), U.S. Pat. No. 4,416,395 (Gaubert), U.S. Pat. No. 4,452,378 (Christine), U.S. Pat. No. 4,602,725 (Malpas et al.), U.S. Pat. No. 6,131,767 (Savage et al.), U.S. Pat. No. 6,446,845 (Steiger) and published application 2005/0121464A1.
The devices of the above identified prior art make use of gravity to enable the liquid within the flexible package to be dispensed from the package. As will be appreciated by those skilled in the art, when the contents of the flexible package has reached a very low level there may not be sufficient static head to enable the dispensing of further amounts, thereby leaving some liquid still within the package. Moreover, the dispensing packages of the prior art making use of gravity as the mechanism for effecting the dispensing operation may not provide precise and repeatable metering of the liquid being dispensed.
Flexible packages for use with pumps also exist in the prior art. See for example, U.S. Pat. No. 4,576,313 (Smith et al.), U.S. Pat. No. 5,819,986 (Last et al.) and U.S. Pat. No. 6,082,584 (Stern).
While the aforementioned packages with fitments may be generally suitable for their intended purposes, they suffer from one or more of the drawbacks, e.g., simplicity of construction, low cost, effectiveness in dispensing repeated metered amounts of liquid, and effectiveness dispensing the entire contents of the package.
In my co-pending U.S. patent application Ser. No. 11/609,064, filed on Dec. 11, 2006, entitled Volumetric Dispensing Fitment And Package Including The Same, which is assigned to the same assignee as this invention and whose disclosure is incorporated by reference herein there is disclosed and claimed a metering dispensing valve fitment for package holding a liquid and a package including such a fitment which overcomes many of the disadvantages of the prior art. That fitment is arranged to be secured to a flexible bag for selectively dispensing a metered quantity of the liquid from the bag. The fitment includes a compressible bulb and a piercing member coupled to the bulb so that when the bulb is compressed the piercing member pierces through the bag to enable a metered amount of the liquid to be drawn into a reservoir in the bulb when the bulb is released. The bulb can then be recompressed to dispense the metered amount of liquid from the reservoir. The dispensing valve also includes an inlet valve to the reservoir and an outlet valve from the reservoir. The fitment may include a pair of barriers to enable it to be sterilized before being secured to the bag to form an aseptic package.
While the fitment of my aforementioned application is suitable for its intended purposes, for some applications a simpler configuration may be desirable. The subject invention addresses that need.